64results about How to "Good preloading effect" patented technology

The invention relates to a preparation method and application of environment-friendly urea resin for laminating plywoods from high water-content veneers. The method for synthesizing the resin is simple, and low in cost; the laminated plywoods can meet the national E1 grade and even E0 grade environmental protection requirements; and the problems of low prepressing performance and water resistance when the high water-content veneers are laminated into the plywoods are mainly solved. In the synthesis of the urea resin, an acid-base-acid-base process is adopted, formaldehyde and polyvinyl alcohol are added at one time, urea is added by three batches, melamine is added by two times, and after ammonia water is added, the ammonia water, the urea, the formaldehyde and urea-form condensate are reacted to generate a series of triazine ring compounds, and the microstructure of the resin is improved. When the resin is cured, the crosslinking density is improved, wet shear strength of the plywoods is obviously improved and the formaldehyde emission is obviously reduced.

The invention relates to a water-based macromolecule-isocyanate straw hard board and a preparation method thereof. Straws of rice, wheat, corn or other crops, a water-based macromolecule-isocyanate adhesive and a straw interface performance modifying agent are used as raw materials, and the straws are treated by section cutting, kneading and modification, adhesive application and heat pressing to produce the water-based macromolecule-isocyanate straw hard board. A mixture ratio of the absolute dry straws to the water-based macromolecule-isocyanate adhesive to the straw interface performance modifying agent by weight is 100 to 10-16 to 0.05-0.15. The straw hard board uses the water-based macromolecule-isocyanate adhesive to replace a pure isocyanate adhesive, radically improves the problems of toxic organic volatiles, poor prepressing performance, adhesion on boards, etc., remarkably reduces cost and really realizes green production, and the raw materials after the treatment of kneading and modification have good prepressing and molding performances and high one-off qualified rate. The water-based macromolecule-isocyanate straw hard board has the characteristics of unique design, long active period, excellent aging, water and heat resisting performances, simple operation, easy availability of equipment, no environmental pollution, easy implementation, etc., and produces huge entironmental, social and economical benefits after the water-based macromolecule-isocyanate straw hard board is popularized.

The invention relates to a preparation method of a formaldehyde-free soybean meal-based wood adhesive for artificial boards, and belongs to the technical field of adhesives. According to the invention, renewable resources, namely soybean meal, are used as raw materials, a water phase is selected as a solvent, and a process step of an alkali-acid two-step method is adopted. Epoxy resin, dicyandiamide, low-molecular-weight polyamide and soybean protein are combined for modification, a chemical reaction is carried out at the same time, and therefore the formaldehyde-free soybean meal-based wood adhesive with very high water resistance and bonding strength is prepared; the adhesive has the advantages of no formaldehyde, low viscosity, good cold pressing performance, low cost, high adhesive strength and the like; the adhesive does not volatilize formaldehyde, phenol or other harmful substances, has the characteristic of no formaldehyde, and is safe and environment-friendly, and the preparedsoybean meal-based wood adhesive is low in viscosity, convenient for applying, good in coating and pre-pressing performance, easy to spray and apply, convenient for repairing of plywood and capable of preventing a shaving board from being scattered, and the problems that a soybean adhesive is high in viscosity and difficult to spray are solved.

The invention discloses a preparation method of E0-level melamine modified urea formaldehyde resin. The E0-level melamine modified urea formaldehyde resin is prepared by the following steps of feeding urea by three batches, and feeding melamine by three batches. The invention also discloses the E0-level melamine modified urea formaldehyde resin and an E0-level melamine modified urea formaldehyde resin adhesive. The method has the advantages that the distribution of the internal molecular structure of the urea formaldehyde resin is changed by the multi-batch feeding type, the prepared resin is added into an adhesive mixer, a formaldehyde removing agent, a reinforcing agent, an acid curing agent and industrial flour are stirred until all the components are uniformly mixed, so as to obtain a mixed adhesive, and the obtained mixed adhesive is applied into the production of parquets; the hot pressing cycle can be shortened, the hot pressing time is shortened from conventional 70-79s/mm to 30-35s/mm under the condition of no change of pressure and temperature parameters, and the utilization rate and production efficiency of a hot press are greatly improved; the release amount of formaldehyde in the prepared plate reaches superE0 level.

The invention provides a high-altitude water injection surcharge load system for bridge support prepressing. The high-altitude water injection surcharge load system comprises a support formwork system, steel tube inclined struts, construction steel ropes, sand bags and waterproof cloth. The steel tube inclined struts are arranged at the two ends of the top of a support formwork; the construction steel ropes are divided into an upper layer and a lower layer and arranged below the bottom face of the top of the support formwork and on a water surface respectively in a transversely-and-oppositely-pulled mode; the sand bags are arranged on flange plates and cross beams of the support formwork; the waterproof cloth is laid on the top of the support formwork and the surfaces of the sand bags. The high-altitude water injection surcharge load system for bridge support prepressing is used high-altitude water injection type prepressing construction combined with sand bag surcharge load conducted for prepressing activities of detection of the overall stability of a framed bent in bridge support erection, the high-altitude water injection surcharge load system for bridge support prepressing can be widely applied to box girder framed bent construction and bridge floor pressing operation of girder bridges, major bridges and the like, and the high-altitude water injection surcharge load system for bridge support prepressing is simple in structure, easy and convenient to operate, capable of saving cost and safe in use.

The invention discloses a soybean meal adhesive for blockboards, and a preparation method thereof. The adhesive comprises, by mass, 22-26 parts of soybean meal powder, 86 parts of a dispersing agent,2-3 parts of trypsin, 1-2 parts of a composite viscosity regulator, 2-3 parts of a branched polymer cross-linking agent and 0.04-0.04 part of calcium phosphate. The preparation method comprises the following steps: K1, performing plasma treatment on the soybean meal powder in a nitrogen atmosphere, then adding calcium chloride and the dispersing agent, performing ultrasonic treatment, adding trypsin, performing treatment at 50-60 DEG C for 20 minutes, cooling, adding phosphoric acid, and performing uniform stirring to obtain a first mixture; and K2, adding calcium phosphate and the branched polymer cross-linking agent into the first mixture, uniformly stirring, adding the composite viscosity regulator, mixing, and regulating the pH value to 9.0 to obtain the soybean meal adhesive for the blockboards. The adhesive is good in water-resistant adhesive property, and ensures the practical performance of the adhesive and the durability of the blockboards.

The invention relates to the technical field of adhesive, in particular to adhesive for indoor plywood. The adhesive comprises, by weight, 50-70 parts of urea resin, 10-20 parts of silicone rubber, 8-15 parts of octyl phenol polyoxyethylene ether, 20-30 parts of polyaspartic acid, 2-4 parts of calcium sulphoaluminate, 10-20 parts of propylene glycol, 8-13 parts of sodium stearate, 6-12 parts of porous inorganic filler, 3-8 parts of polyvinyl acetate emulsion, 1-5 parts of nano-silica and 5-10 parts of water. The adhesive for the indoor plywood is good in viscosity, has the antiseptic and anti-static functions and contains lower formaldehyde, the water resistance and aging resistance of the adhesive are improved greatly, and the service life of the adhesive is prolonged by half a year to one year. The adhesive is mainly applied to bonding of the inner plywood.

The invention discloses a flour composition for urea resin and a preparation method and application thereof. The flour composition is prepared from, by weight parts, 100 parts of mixed plant fiber powder having undergone EM bacterium solid fermentation hydrolysis treatment, 0.15-0.25 part of sodium carboxymethyl cellulose, 4-7 parts of calcium carbonate powder and 8-12 parts of flour. The mixed plant fiber powder having undergone the EM bacterium solid fermentation hydrolysis treatment is prepared according to the following method: matching raw materials which are, by weight parts, 50-60 parts of wood powder, 20-35 parts of corn stalk and 10-20 parts of cassava residue powder, placing the three kinds of powder in a stirring mixer, performing spraying to add EM bacterium liquid with stirring, performing stirring evenly, enabling the number of effective bacterium in the materials to be 0.5-1*10<10> CUF/kg, enabling the moisture content to be 40-50 wt%, and performing fermentation until the measured pH of a sample is 4.0-4.5. The flour composition for urea resin is used for plywood production, can save plenty of grains and have good prepressing performance, the adhesive strength and water resistance of a plywood product are improved compared with the use of wheat flour, and the formaldehyde emission is reduced.

The invention discloses a vertical roller mill with material prepressing and positioned blanking and a vertical roller milling method. A material layer prepressing device and a concentrated blanking device are arranged in an inner cavity of a mill body; the material layer prepressing device includes a grinding roller; rotating shafts are arranged at two ends of the grinding roller, and are connected with connecting rods through bearings and bearing bases; the connecting rods are connected with a support frame; the support frame is fixed on the wall of the inner cavity of the mill body, and is positioned two adjacent grinding rollers in the inner cavity of the mill body; the upper end of an extension pipe of the concentrated blanking device is connected with the lower end of a blanking inner cone hopper; the lower part of a fixed plate at the lower part of an inner cavity of the extension pipe is connected with the upper part of a connecting plate; the lower part of the connecting plate is connected with a scraper; and a gap is formed between the lower end surface of the scraper and the upper end surface of a milling disc. The vertical roller mill is reasonable in design, accurate in blanking point and excellent in material paving and prepressing effects, and can improve the powder milling quality.

The invention belongs to the technical field of processing anti-corrosion plywood, and in particular relates to a preparation method of weather-resistant anti-corrosion plywood, including a veneer anti-corrosion treatment method of vacuum immersion in anti-corrosion liquid, a method of drying anti-corrosion veneer by electromagnetic wave drying and an adhesive preparation. Compared with the prior art, the present invention has the following advantages: the antiseptic liquid in the present invention is friendly to the environment and has good resistance to various microorganisms. Through the cooperation of vacuum conditions, the antiseptic liquid has good permeability in the veneer and can Uniform, and then use electromagnetic wave sealing treatment, which can make the ingredients in the antiseptic solution better combined in the veneer, which can effectively reduce the loss of active ingredients and improve the durability of the antiseptic effect; the adhesive can avoid the problem of excessive aging and avoid After hot pressing, the glue is opened, so that the obtained plywood has a stable structure, good weather resistance, effective and long-lasting anti-corrosion effect, and remarkable economic benefits.

Disclosed are a vacuum preloading device with a sandbag cushion layer, and a construction method thereof. The vacuum preloading device comprises a vacuum pump, a vertical sandbag layer, a horizontal sandbag layer, geotextile, a clay sealing layer, a polyethylene sealing film and a split water sealing layer. The vertical sandbag layer, the horizontal sandbag layer, the geotextile, the clay sealinglayer, the polyethylene sealing film and the split water sealing layer are sequentially laid on the soil surface from bottom to top. A plurality of vacuum tubes communicated with the vacuum pump are embedded in sandbag gaps of the longitudinal sandbag layer, and a plurality of plastic drainage plates are fixedly inserted into the bottoms of sandbags of the vertical sandbag layer; the polyethylenesealing film is hermetically laid on the upper surfaces of the clay sealing layer and a film pressing groove; the split water sealing layer is arranged on the upper surface of the polyethylene sealingfilm. The vacuum preloading device and the construction method thereof have the advantages that the arrangement mode of conventional horizontal drainage bodies is changed, the flexible water-permeable and sand-permeable sandbags position the vacuum tubes and the plastic drainage plates and apply a certain downward pressure on the soil surface, and the plastic drainage plates, the sandbags and thevacuum tubes are assembled integrally; the vacuum preloading device has the advantages of stable shape, capability of not being affected by sedimentation and convenience in construction.

The invention relates to the field of bridge engineering and discloses a preloading operation method of a high-altitude tower column crossbeam support, which is suitable for cable-stayed bridges, suspension bridges and the like. The method comprises the following steps: S1, a hinged preloading force transmission structure is manufactured. The hinged preloading force transmission structure is formed by a hinged diagonal brace A and a hinged diagonal brace B. The force transmission bracket is connected with a steel pin correspondingly; S2, construction is carried out on that tower column and a support is erected, wherein the tower column is provided with a tower column reserve hole for pas steel wire rope, the horizontal included angle of the tower column reserve hole is 0 DEG, and the bracket legs of the support are embedded in advance and the upper frame bracket legs are embedded in the tower column during construction. After the bracket corbel is finished, the bracket is erected on the bracket corbel, and the upper bracket is erected between the upper bracket corbel. S3, hinged preloading force transmission structure is installed, one end of that steel wire rope is connected withthe articulated preloading force transmission structure, and one end passes through a pre-reserved hole of a tower column; S4, the jack is installed, using the pulling force F (i) n (/i) exerted on the wire rope by the jack; S5, the hinged preload transfer structure and the jack are removed to complete the preload of the bracket.

The invention discloses a preparing method of earthnut shell liquidation and adhesive modifier, which comprises the following steps: removing soil and foreign matter on the surface of earthnut; drying; disintegrating; mixing the earthnut shell powder and alcohol evenly; adding into inorganic middle strong acid or organic strong acid; reacting for 1. 0-4. 0 h with temperature at 120-160 deg. c; adding into caustic soda solution; adjusting pH value to neutral; decreasing the temperature below 40 deg. c; putting into material; getting the alcohol of earthnut shell powder or carbinol liquefied product; getting lumber adhesive agent modifier for glued board in room; increasing water resistance of gummed product; decreasing methyl aldehyde delivery quantity; producing glued board with urea-formaldehyde glue. This adhesive possesses distinctive prepressing effect, which bonding strength at 1. 3MPa and formaldehyde delivery quantity at 4. 5mg/L.